Six Commonly Missed Diagnoses: B12 Deficiency

Posted 05/14/2012

You’re pretty sure you know your body and you tell your doctor you’re just not feeling right. You’re tired, maybe a little depressed, a bit achy. Maybe your digestion is “off.” The list of foods you can’t seem to enjoy is definitely longer. Your doctor’s empathic, not at all dismissive of your symptoms, but after a physical exam and some apparently appropriate tests she can’t find anything really wrong.

On the surface, this is reassuring. After all, the main reason we do go to doctors is to ascertain that nothing serious is going on. Still, could she be overlooking something?

After decades of treating patients with longstanding but undiagnosed chronic symptoms, here’s the first of six overlooked diagnoses I see most frequently in our patients at WholeHealth Chicago.

Low Levels of Vitamin B-12
One of the eight B vitamins, B-12 is involved in the metabolism of every cell in your body. Years ago B-12 was called “maturation factor” because cells need B-12 to mature from being young and ineffectual whippersnappers to fully functioning and mature.

B-12 deficiencies affect three major systems in your body: your blood, nervous system, and, less often, gastrointestinal tract. These three are targets because their cells either have a high turnover rate (blood and intestinal lining) or need a lot of B-12 to function smoothly (nervous system). The symptoms of low B-12 levels are related to each of these areas.

  • Low B-12’s effect on your blood is a specific type of anemia called megaloblastic anemia (as distinct from the more common iron deficiency anemia). A megaloblast is an immature, undeveloped red blood cell, large and bulky (megalo=large, blast=immature form). Remember, B-12 is needed for this cell to mature, so with insufficient B-12 megaloblasts accumulate in your blood. Symptoms are the same as for anemia from any cause, including fatigue, breathlessness, and lightheadedness. Your skin becomes a pale yellow, most likely because the red cells that do make it to maturity are very fragile and easily broken, releasing their yellow bilirubin pigment.
  • In your nervous system, B-12 deficiency causes symptoms affecting your nerves (numbness, tingling, tremors, balance problems) and your mind (depression, brain fog, mood swings, and, in rare cases, hallucinations and psychosis).
  • In your gastrointestinal tract, you might experience digestive symptoms and weight loss because you’re not absorbing food efficiently.

The irony is that with all these there’s usually just one predominant symptom, and making a connection to low B-12 can easily be delayed until other symptoms start to appear. For example, if your only symptom is tingling in your hands, you might undergo all sorts of diagnostic tests before your doctor thinks “Maybe we should check her B-12 level.”

What causes B-12 deficiency?
The list of causes is lengthy, but by far the most frequent culprit is a dietary one. Vegetarians who aren’t paying attention to the B-12 in their food choices will have downward-drifting B-12 levels, and virtually all vegans not taking Vitamin B-12 supplements ultimately develop deficiencies. Even the various vegan organizations acknowledge it’s not possible to get adequate B-12 while following a strictly vegan diet, and that’s because the richest sources are animal products.

Other causes of B-12 deficiency include pernicious anemia, an uncommon (and spookily named) autoimmune disease that destroys parietal stomach cells. These cells produce a substance called intrinsic factor, necessary for B-12 absorption. Also, since you need stomach acid to absorb B-12, long-term use of acid-suppressing proton pump inhibitors (Nexium, etc.) can lead to B-12 deficiency, as can chronic intestinal conditions like Crohn’s disease, celiac disease, and intestinal parasites.

The missed diagnosis
The main danger of missing this diagnosis is that (while quite rare) the damage to your nerves and even brain can be permanent. Other serious consequences: your anemia can get so severe it causes heart failure and collapse. Or you could be misdiagnosed with a major depressive disorder or even psychosis and take unneeded psychiatric medications for months (or years) before someone notices you look yellow-ish and you’re finally diagnosed with megaloblastic anemia.

There are four reasons why this diagnosis is missed:

  1. Although it’s not an expensive test, B-12 isn’t measured during routine blood tests. Doctors generally don’t order a B-12 evaluation if there’s no evidence of anemia (which would be picked up on a routine blood test). However, the fatigue and nervous system and gastrointestinal symptoms can precede anemia by months.
  2. Doctors rarely ask (and patients rarely volunteer) information about their eating habits. In medical school, we’re taught that the US diet is “plenty good enough to prevent any vitamin deficiencies.” To which I now respond, “Ha!” I agree most of us eat plenty of food (obesity levels are still on the rise), but it’s often food whose nutritional value has been castrated. Also, all vegetarians and vegans should be regularly tested for possible B-12 deficiency, but if your doc doesn’t know your eating habits you won’t be tested.
  3. Like many blood tests, there’s considerable disagreement about normal levels of B-12. Most labs test B-12 levels between 200 pg/ml (picograms per milliliter) and 800 pg/ml. Someone at 250 pg/ml would be classified as normal, but symptoms can start appearing at 350 pg/ml. In Japan, normal B-12 was recently raised to 500 pg/ml and higher. We’ll see this type of erroneous overreliance on “normals” in other frequently missed diagnoses, like hypothyroidism, vitamin D deficiency, gluten intolerance, adrenal fatigue.
  4. Taking the B vitamin folic acid (folate) or eating a lot of folate-containing foods without adding B-12 can actually mask the symptoms of a developing B-12 deficiency. Although folate will keep your blood count normal even if your B-12 is falling, the folate will not protect your brain and nervous system. You’ll have no evidence of megaloblastic anemia (because of the folate), but your symptoms of numbness, tingling, balance problems, and emotional issues will continue unchecked. By eating so many folate-containing green vegetables, beans, and lentils, vegetarians and vegans inadvertently mask their own slowly developing B-12 deficiency.

Treatment is easy
It’s virtually impossible to take too much B-12 as any excess of this water-soluble vitamin is eliminated via urine. Nutritional guru Alan Gaby, MD, has commented that the only way too much B-12 will kill you is if you fill your bathtub with it and drown.

Foods high in B-12 are animal products: meat, poultry, seafood, dairy, and eggs, with eggs having the least. Because all animals store B-12 in their livers, eating liver is an excellent (though not particularly popular) treatment for B-12 deficiency. Your grandmother or great-grandmother likely remembers a time when her doctor told someone in the family to eat more liver.

And since people with low B-12 are likely to also have gastrointestinal symptoms that interfere with B-12 absorption, the best way to quickly increase (and maintain) B-12 levels are with B-12 injections, chewable tablets, or the recently released nasal sprays and skin patches.

In my own practice, a deficient patient receives a series of four B-12 injections (or four B-12 containing Meyer’s Cocktails) and also starts (and maintains herself on) a daily B-12 chewable tablet. Usually within a month her levels are back to normal.

There’s more to come in the Commonly Missed Diagnoses series. Next week: overlooked diagnosis #2, vitamin D deficiency

Be well,

David Edelberg, MD

Posted in Blog, Integrative Medicine, Knowledge Base, S Tagged with: ,
422 comments on “Six Commonly Missed Diagnoses: B12 Deficiency
  1. Surgery doctors need to understand more these days – I did work in a surgery so I am familiar with the routine but when I changed surgeries to become a driving instructor I was disappointed with a couple of them!!

  2. Excellent information. Just posted this on an ALS forum.

  3. wolf max says:

    thanks for that. i’m getting gradually more cold/numb in hands/feet and fatigued, etc etc. and full of joint pain/injuries, so luckily came to realize i have morton’s foot which comes from a p5p deficiency, so to prove if quackery or legit, i chose to test b2 b6 b9 b12 and homocysteine and found off charts high homocysteine, off charts low b2 which were expected and apparently indicate inability to convert b6 to p5p thus no p5p to convert homocysteine etc. and likely others deficiencies inherent. anyway, i’m looking for a similar article for b2 deficiency and vitamin d. thanx.

  4. Debbie Johnson says:

    Wow! Very helpful information. Excellent explanation that is easily understood.

  5. Adeline Mikka says:

    Want to know more. I have been diagnosed with a brain cloud but all subsequent tests have “normal” results. What can this be? I am female 67 years old.

  6. cliffmaurer says:

    This can be due to a variety of causes. Do you have access to a functional or integrative medicine physician? If you’re in the Chicago area, we’re happy to help.
    -Dr M

  7. Alison says:

    Thank you for the insightful article. Very interesting about the GI manifestations. However, contrary to the opinion of Dr. Alan Gaby, it is possible to overdose on B12 for those who have polycythemia. Often, a diagnosis of polycythemia is not uncovered until a person starts to replenish depleted B12 stores. This can become a crisis of thrombosis very quickly, particularly if IVs are given. Possibly high dose niacin might reverse this, not exactly sure though. Other than that, immediate and perhaps ongoing, phlebotomy must be performed.

  8. jessica says:

    I know that this article is about lack of b12 but i need help in finding information about high b12 levels. my son is 8 and had bloodwork done on march 8th that read that his b12, ferritin serum and platelet levels are all too high. he did catch a bad cold around the 25th of feb. bad enough for me to have to take him to the hospital for a fever that was 103. im not sure if the b12 elevated to fight off the cold and was still in his system on the 8th and just happened to show in his results or should i be scared because everything i read says that high b12 means serious problems. can you help me please?

  9. Dr E says:

    Having a high B12 level in itself is not dangerous but certain medical conditions can cause elevated B12 levels. If your son is NOT taking any supplements containing B12 then the cause of his high levels should be investigated. Virtually all the high B12 levels I see in my practice are caused by patients taking a lot of it. Fortunately this is harmless

  10. Michelle says:

    Hi i was diagnosed of going through the menapause 2years ago.i have been feeling drained not tiered but physical drained moody and depressed headaches joint pain out of breath memory loss blurry vision .I have said that there is something i cant put my finger on a couple of my friends mentioned b12 . I haven’t heard of it at all but after looking it up i think it explains a lot of my symptoms.i am at the drs on Monday and i am going to ask for the test

  11. Michelle says:

    Hi i have blurry vision headaches very drained feel very low joint pain and very bad memory .I have been told by friends to have a b12 test so i go on Monday I’ve never heard of it before .

  12. Jayne says:

    Hi, I have been on B12 shots and taking sprays, creams and lozenge for two to three years. Ever time I miss a day, I shake or start to cry over anything and occasionally wake up with numb or tingling hands. I have Hashimoto’s, Celiac, and Anemia which I am in treatment for. My question is: is my B12 deficiency chronic? Could it be Pernicious Anemia? And next: what can I do to reverse this issue? Could a B12 deficiency have anything to do with a chronic Magnesium deficiency?

  13. Dr. R says:

    Hi Jayne. It is probably best to speak to your PCP regarding the low B12 and associated health conditions. He/she knows your history and can properly assess your current laboratory tests.

  14. Pete says:

    I have had warts on my hands for a few years could this be B12 deficiency ,I have a low blood count.

  15. Dr E says:

    In theory, yes.B-12 is involved in a healthy immune system and low B12 could prevent your immunity from functioning efficiently, predisposing you to viral infections like warts.
    BTW, my favorite wart treatment is the stomach med Tagamet (sold over the counter), one tab twice a day.

  16. Patti Woodbury Kuvik says:

    As a cancer patient/survivor (small cell lung cancer, medullary thyroid cancer) I keep a close watch on my blood work results. No one was concerned with my high B-12 level. I had stopped any B supplements for a week before the test and – before that had only been taking low levels of B-12 or B complex – not both. When I was referred to a colo-rectal surgeon for a spot that had lit up on my regular PET scan, he was the first to acknowledge a problem. Apparently h had read the same research I found on PubMed correlating high B-12 (excessive intake ruled out) with colon tumors and the higher the level, the greater the likelihood of malignancy. My B-12 was double the “high normal” and in the study’s range for high likelihood for malignancy. The fast growing nasty looking (surgeon gave me photos) golf ball size tumor turned out to be “pre-cancerous” but just barely – another couple of months it might have been a different story.
    Colon cancer can be aggressive and fast growing and is so often caught in late stages when it becomes difficult and unpleasant to treat. If elevated B-12 levels can help with detection as the study suggests, it’s a pretty simple and relatively inexpensive test. (Just make sure you skip any B vitamins for several days to allow for a wash out before having blood checked.) While neither a diagnosis nor a confirmation of a possible problem, an excessive level should provide enough suspicion to merit further imaging tests and/or a colonoscopy.

  17. christy says:

    I have been suffering from numbness in both hands for the past two years.After i removed norplant.i have been to the hospital but the doctor said it can not be due to the norplant cause its affecting my both hands.please I need help on what to do

  18. atara schimmel says:

    The fact that serum levels have returned to normal after a few injections is irrelevant when treating a person that is B12 deficient with psychiatric and neurological symptoms. Injections must be continued until there is no further improvement. Sally Pacholok’s book ‘Could it Be B12?’ is the most thorough and up to date book on B12 deficiency. Anyone that thinks they may be struggling with a deficiency will benefit tremendously by reading this book.

  19. cliffmaurer says:

    Hi Christy – If you’re in the Chicgao area, I or any of our nurse practitioners could see you to help you figure this out. If you live elsewhere, I recommend this website to help you find a practitioner that can help:

    Best to you,
    Dr. Maurer

  20. Rubén says:

    Hi dr. I had last year b12 deficiency around 263 i has right foot numbness. I took 3 inyections of b12 and it realy help. On march my b12 784 on April 1111. One month ago on my right ear i have acouphene pulsatil 24hrs. I want to know if low b12 can provoke this ear problem. Now my b12 is 438. And my platelets are 148m . Thanks please advice

  21. Vicky says:

    Hi there… weeks ago my neurologist found folic and B12 issues ref to GP to prescribe. Managed to get the folic acid but have to wait for another blood test to show why B12 is low. In the mean time spent four days in hospital due to left side numbness and hallucinations. And the worst headache ever.. had MRI and CT scan brain structure normal thank god.. could all these issues be down to B12?. My blood test to find out why B12 is low is this coming Friday… numbness still remains even though I’m now home. Can anyone relate to this. I live in the UK

  22. Dr E says:

    Hi Ruben
    It is very unlikely the low B12 is related to your ear issues especially as the symptoms occurred when your B12 had returned to normal
    Hi Vicki
    Low B12 is indeed associated with your symptoms. Determing why your B12 is low can be accomplished with some simple tests. If you are unable to absorb it through your GI system, you’ll simply need regular B12 injections

  23. duffydan says:

    I am 50 and I have had trigeminal neuralgia since 2008, although I was not diagnosed until 2010. I had never had bloodwork done checking if I might be deficient in vitamin B until last mint when I found out I have the MHFKR gene mutation. The thin-cut MRI that I have had does not show a collapsed nerve anywhere. I do have a cousin that have TN as well. I’m curious if this “might” be a factor.

  24. Dr E says:

    MTHFR people have difficulty getting enough B-12 in their cells. Low B12 is associated with a variety of neurological problems including trigeminal neuralgia. Your doctor can give you injections of methylcobalamin B12 which will give you good B12 levels. The usual B12 is cyanocobalamin which simply doesn;t work as well in this situation

Leave a Comment